Stealing Data From Computers Using Heat

Air-gapped systems, which are isolated from the Internet and are not connected to other systems that are connected to the Internet, are used in situations that demand high security because they make siphoning data from them difficult.
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But security researchers at Ben Gurion University in Israel have found a way to retrieve data from an air-gapped computer using only heat emissions and a computer’s built-in thermal sensors.

No matter how secure you think a computer is, there’s always a vulnerability somewhere that a remote attacker can utilize if they’re determined enough. To reduce the chance of sensitive material being stolen, many government and industrial computer systems are not connected to outside networks. This practice is called air-gapping, but even that might not be enough. The Stuxnet worm from several years ago spread to isolated networks via USB flash drives, and now researchers at Ben Gurion University in Israel have shown that it’s possible to rig up two-way communication with an air-gapped computer via heat exchange.